fix: CI workflows — add nodejs, clean up migration runner

deploy.yaml: add nodejs install (required for actions/checkout)
migrate.yaml: rewrite migration runner
  - Use PGHOST/PGUSER/PGPASSWORD env vars (no inline -h/-U/-p flags)
  - ON_ERROR_STOP=1 for strict error handling on push
  - || true for dispatch (idempotent full replay)
  - Verify schema after apply
  - fetch-depth: 2 for diff detection

.gitea/workflows/deploy.yaml

@@ -15,8 +15,10 @@ jobs:
     name: Tag & Push Latest
     runs-on: rust
     steps:
-      - name: Install Docker
-        run: apt-get update && apt-get install -y docker.io
+      - name: Install Node.js and Docker
+        run: |
+          apt-get update
+          apt-get install -y nodejs docker.io
 
       - name: Checkout code
         uses: actions/checkout@v4